I’m sure that many of you have been in relationships where you and your significant other are so completely at ease with each other than you have no reservations about teasing or mocking each other good-naturedly. But you know how sometimes when you’re giving your boyfriend or girlfriend sh*t and you accidentally cross that line between what is acceptable to joke about, and what hits too close to home and ends up hurting your S.O.’s feelings? Then you find yourself in a “I was just kidding!” argument spiral that invariably leads to you sleeping on the couch because you joked that your girlfriend’s toes were gnarly?

That’s what’s at stake in Catastrophe, Amazon’s new series borrowed from Britain’s Channel 4 starring and written by Rob Delaney and Sharon Horgan. Only in Catastrophe, the characters keep pushing beyond that line, and there’s rarely ever any repercussions. Hogan and Delaney (who plays characters named Sharon and Rob) are brutal to each other, and every laugh comes with a slight wince, as though bracing for a narrative backhand.

The show can best be described as Knocked Up meets FX’s You’re the Worst, with a the sense of humor that is very much along the same lines as the biting, hilarious comedy of the latter series.

Rob, an American, meets Sharon in a London bar while he’s on a business trip. They have a torrid, meaningless three-day fling and bid adieu to one another with no intention of ever seeing one another again: No harm, no foul. It was a good time. The sex was great. See you later!

A few weeks later, however, Rob gets a call from Sharon informing him that she’s pregnant. Oops. Abortion is on the table, but Sharon decides against it because she’s 42 and may not have many more opportunities to have a child. Rob, who insist upon being an upstanding American male, decides to move to London and help her have a baby. They quickly get engaged, not out of love, but so that he can stay in the country.

Catastrophe is essentially a romantic-comedy in reverse: There’s a pregnancy, then they get married, and then they get to know one another to see if they can fall in love. The courtship is set against the backdrop of a pregnancy — one that turns out to be somewhat complicated, given Sharon’s age — which adds an entirely new layer of complication to their relationship, along with Rob’s need to remain employed in London.

That might make it sound more dramatic than you might expect for a comedy, but it’s not. Mostly, it’s really fucking funny. The humor is scabrous and has real fangs to go along with some genuine chemistry between Delaney and Horgan who, in case I haven’t strongly suggested it enough, is absolutely dynamite. She’s like Kathryn Hahn and Aya Cash smashed together into a delightfully charming, quick-witted lust factory (she is, in fact, a newly added member on my Five Freebies list). She is amazing, and already well known to Brits, having starred in several sitcoms we Americans have badly remade (“Free Agents,” where her character I believe was played by Hahn) or attempted to remake (“Pulling”).

It’s also perfect summer viewing: It’s available for binge-watching on Amazon Prime there are only six 25-minute episodes, and you can probably knocked it out in one or two sittings (it’s also been picked up for a second season). Give it a shot. It’s amazing goddamn TV.